There are stories that when the Skype lads met with Whitman, they whiteboarded all sorts of ideas about the future. One can only speculate that much of the perceived value in the acquisition comes from that creative energy.

Personally, I'm left guessing whether eBay wants to incorporate Skype's hierarchical peer-to-peer communications model into their auction technology. In effect, to try to use the bidder's and seller's (and even "innocent third parties" according to the Skype model) computers rather than eBay's own servers.